Nail buffer



FIG. 1 is a perspective view of my design for a nail buffer;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a top view thereof;

FIG. 5 is a bottom view thereof;

FIG. 6 is a left side view thereof; and,

FIG. 7 is a right side view thereof.

The outermost broken line indicates a portion of the article and the innermost broken line indicates the boundary of the claimed design. None of the broken lines forms part of the claimed design. 

The ornamental design for the nail buffer, as shown and described. 